On Tue, 23 Feb 2021 at 12:19, Paul Fertser <fercerpav@xxxxxxxxx> wrote: > > Hello Adrian, > > On Tue, Feb 23, 2021 at 01:01:09PM +0200, Adrian Hunter wrote: > > On 23/02/21 11:32 am, Paul Fertser wrote: > > > Hello Ulf, > > > > > > On Tue, Feb 23, 2021 at 10:23:28AM +0100, Ulf Hansson wrote: > > >>> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > > >>> index f5dedb7f9b27..9adf735391fa 100644 > > >>> --- a/drivers/mmc/core/mmc.c > > >>> +++ b/drivers/mmc/core/mmc.c > > >>> @@ -426,8 +426,7 @@ static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd) > > >>> /* EXT_CSD value is in units of 10ms, but we store in ms */ > > >>> card->ext_csd.part_time = 10 * ext_csd[EXT_CSD_PART_SWITCH_TIME]; > > >>> /* Some eMMC set the value too low so set a minimum */ > > >>> - if (card->ext_csd.part_time && > > >>> - card->ext_csd.part_time < MMC_MIN_PART_SWITCH_TIME) > > >>> + if (card->ext_csd.part_time < MMC_MIN_PART_SWITCH_TIME) > > >>> card->ext_csd.part_time = MMC_MIN_PART_SWITCH_TIME; > > >>> > > >>> /* Sleep / awake timeout in 100ns units */ > > >>> > > >>> I do not see any more warnings on my system. > > >> > > >> That looks like the correct fix to the problem. Do you want to send a > > >> proper patch that I can pick up or do you prefer if help to do it? > > > > > > I've sent this as a diff precisely because 1c447116d017 was so > > > explicit about special-casing zero ext_csd timeout value, so I thought > > > probably Adrian can provide the rationale for that. I'd prefer to wait > > > for his feedback before sending a formal patch. Does this make sense? > > > > Zero means indefinite. Might be safer to use a higher value than > > MMC_MIN_PART_SWITCH_TIME for that case. The maximum GENERIC_CMD6_TIME is > > 2550 ms. > > Thanks for the clarification! I would guess that most likely than not > when whoever defines that value to be zero it means "I do not > care/know" rather than "the timeout must be set to more than 2550 ms, > too bad 8 bits are not enough to represent that". I'd say setting it > to DEFAULT_CMD6_TIMEOUT_MS should be safe enough since it worked > before. Hmm. The DEFAULT_CMD6_TIMEOUT_MS is intended to override the ext_csd->generic_cmd6_time, in case it's not defined in the register. Perhaps it's reasonable to think that eMMC vendors specify the GENERIC_CMD6_TIME, but may skip to specify other timeouts, like the PARTITION_SWITCH_TIME. In that case, should we use the specified GENERIC_CMD6_TIME, rather than always default to DEFAULT_CMD6_TIMEOUT_MS? Kind regards Uffe
